DNA Typing with 17 Microsatellites for Parentage Verification of Racehorses in Japan

Abstract

A microsatellite DNA typing with 17 microsatellites (mSats) including nine international minimum standard mSats was developed for parentage verification of racehorse, and 1308 racehorses, Thoroughbred and Anglo-Arab, were analysed using the 17 mSats. Reasonable reliability and reproducibility of genotyping were observed based on data of sizing precision of PCR fragments. On both breeds, discrimination and exclusion probabilities were estimated to be approximately 6×10-17-10-18 and over 0.99999, respectively. Therefore, it is theoretically suggested that the present DNA typing has high ability for individual identification and parentage verification. Actually, true paternities for 367 double mating cases could be verified using the 17 mSats. Furthermore, to confirm potentiality for resolution of multiple mating, paternity testing was simulated by selection from 502 provisional stallions in 367 mare-offspring pair cases. Decision rate for one candidate sire with the 17 loci was 97.3% indicating high ability for resolution of multiple mating. These data suggest that the present DNA typing is quite suitable to parentage verification for racehorses in Japan.